The conventional electric vehicle is generally operated by a motor having a relatively small horsepower, with the power source of the motor being a battery set. Such conventional electric vehicle as described above is inefficient at best in terms of performance, especially in an uphill situation. The operational inefficiency of the conventional electric vehicle is attributable to two factors, one of which is the small horsepower of the motor, with the other factor being the fact that only one end of a wheel axle is driven by the motor via a transmission member and a sprocket.